Re: [PATCH 2/2] spi: a3700: Remove endianness swapping for full-duplex transfers

From: Gregory CLEMENT
Date: Wed Jan 24 2018 - 09:24:04 EST


Hi Maxime,

On mer., janv. 24 2018, Maxime Chevallier <maxime.chevallier@xxxxxxxx> wrote:

> Fixes the following sparse warnings :
> line 767: warning: incorrect type in assignment (different base types)
> line 767: expected unsigned int [unsigned] [assigned] [usertype] val_out
> line 767: got restricted __le32 [usertype] <noident>
> line 776: warning: cast to restricted __le32
>
> This takes advantage of readl/writel to do the endianness reordering,
> and removes an extra variable in the function.
>
> Fixes: f68a7dcb91b7 ("spi: a3700: Add full-duplex support")
> Signed-off-by: Maxime Chevallier <maxime.chevallier@xxxxxxxx>

As for the previous patch:

Reviewed-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxxxxxxxxx>

Thanks,

Gregory> ---
> drivers/spi/spi-armada-3700.c | 13 ++++++-------
> 1 file changed, 6 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/spi/spi-armada-3700.c b/drivers/spi/spi-armada-3700.c
> index 43ee0b56fe1c..7dcb14d303eb 100644
> --- a/drivers/spi/spi-armada-3700.c
> +++ b/drivers/spi/spi-armada-3700.c
> @@ -747,7 +747,7 @@ static int a3700_spi_transfer_one_full_duplex(struct spi_master *master,
> struct spi_transfer *xfer)
> {
> struct a3700_spi *a3700_spi = spi_master_get_devdata(master);
> - u32 val_in, val_out;
> + u32 val;
>
> /* Disable FIFO mode */
> a3700_spi_fifo_mode_set(a3700_spi, false);
> @@ -761,21 +761,20 @@ static int a3700_spi_transfer_one_full_duplex(struct spi_master *master,
> a3700_spi_bytelen_set(a3700_spi, 1);
>
> if (a3700_spi->byte_len == 1)
> - val_out = *a3700_spi->tx_buf;
> + val = *a3700_spi->tx_buf;
> else
> - val_out = cpu_to_le32(*(u32 *)a3700_spi->tx_buf);
> + val = *(u32 *)a3700_spi->tx_buf;
>
> - spireg_write(a3700_spi, A3700_SPI_DATA_OUT_REG, val_out);
> + spireg_write(a3700_spi, A3700_SPI_DATA_OUT_REG, val);
>
> /* Wait for all the data to be shifted in / out */
> while (!(spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG) &
> A3700_SPI_XFER_DONE))
> cpu_relax();
>
> - val_in = le32_to_cpu(spireg_read(a3700_spi,
> - A3700_SPI_DATA_IN_REG));
> + val = spireg_read(a3700_spi, A3700_SPI_DATA_IN_REG);
>
> - memcpy(a3700_spi->rx_buf, &val_in, a3700_spi->byte_len);
> + memcpy(a3700_spi->rx_buf, &val, a3700_spi->byte_len);
>
> a3700_spi->buf_len -= a3700_spi->byte_len;
> a3700_spi->tx_buf += a3700_spi->byte_len;
> --
> 2.1.4
>

--
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com